Search results for " ai"
showing 10 items of 2441 documents
Red and far-red sun-induced chlorophyll fluorescence as a measure of plant photosynthesis
2015
Remote estimation of Sun-induced chlorophyll fluorescence emitted by terrestrial vegetation can provide an unparalleled opportunity to track spatiotemporal variations of photosynthetic efficiency. Here we provide the first direct experimental evidence that the two peaks of the chlorophyll fluorescence spectrum can be accurately mapped from high-resolution radiance spectra and that the signal is linked to variations in actual photosynthetic efficiency. Red and far red fluorescence measured using a novel airborne imaging spectrometer over a grass carpet treated with an herbicide known to inhibit photosynthesis was significantly higher than the corresponding signal from an equivalent untreated…
Computational strategies for the design of new enzymatic functions
2015
In this contribution, recent developments in the design of biocatalysts are reviewed with particular emphasis in the de novo strategy. Studies based on three different reactions, Kemp elimination, Diels–Alder and Retro-Aldolase, are used to illustrate different success achieved during the last years. Finally, a section is devoted to the particular case of designed metalloenzymes. As a general conclusion, the interplay between new and more sophisticated engineering protocols and computational methods, based on molecular dynamics simulations with Quantum Mechanics/Molecular Mechanics potentials and fully flexible models, seems to constitute the bed rock for present and future successful desig…
Preliminary results about the breath of passive smokers and vapers based on the use of portable air monitoring devices
2016
Abstract Preliminary studies were made on the effect of both, classical smoking and electronic cigarettes (ECs) vaping, based on the quality of the indoor air and the breath of passive smokers. Portable air monitoring devices were used to evaluate carbon monoxide (CO), carbon dioxide (CO2), particulate materials (PM), formaldehyde and volatile organic compounds (VOCs) in indoor air and breath of active and passive smokers and vapers. As preliminary results, it can be observed that the major part of PMs liberated in classical smoking and ECs vaping correspond to the lowest size, which is the most dangerous for human health. However, the number of smallest PMs formed during vaping is around 5…
First aid in dental trauma in pediatric age
2014
The knowledge of the right management of dental traumas is very important for the pediatrician due both to their high incidence in this age group and to prevent further pathologic events related. Several studies indicate that in industrialized countries, about one in five children have had a traumatic dental injury to permanent teeth before leaving school. Prevalence of injured teeth presented in the literature varies from 10 to 51% [1]. The pediatrician, more than any other health professionals, should have the necessary knowledge to ensure correct and professional advices for all issues concerning the child's health [2]. Most of the available literature emphasizes that awareness of the co…
Energy performance evaluation of a demo solar desiccant cooling system with heat recovery for the regeneration of the adsorption material
2012
Abstract Since July 2008, a Solar Desiccant Evaporative Cooling (DEC) system has been operating as a test plant at the solar laboratory of the Dipartimento di Energia (ex DREAM) of the University of Palermo. The system is composed of an air handling unit (AHU) designed for ventilation of the laboratory coupled with a radiant ceiling that provides most of the required sensible cooling/heating energy. Flat plate collectors deliver part of the regeneration heat of the desiccant wheel during the summertime and are used for space heating during the wintertime. The system was designed for high humidity loads because of the typical climate conditions at the site and the need to support a radiant c…
Life Cycle Assessment Performance Comparison of Small Solar Thermal Cooling Systems with Conventional Plants Assisted with Photovoltaics
2012
Abstract Life Cycle Assessment (LCA) allows for the consideration of energy consumption and environmental impacts associated with all the stages of a product's life, from the cradle to the grave . Starting from the results obtained in the IEA SHC Task 38 framework for the LCA of small solar assisted heat driven chillers, the application of such methodology has been extended to systems with a conventional compression chiller assisted by a photovoltaic plant. This study aims to provide a more comprehensive investigation through a comparison of these two families of solar assisted cooling systems (with solar thermal or PV), which is an important topic for studies concerning the research of eff…
Energy and economic assessment of desiccant cooling systems coupled with single glazed air and hybrid PV/thermal solar collectors for applications in…
2009
Abstract This paper presents a detailed analysis of the energy and economic performance of desiccant cooling systems (DEC) equipped with both single glazed standard air and hybrid photovoltaic/thermal (PV/t) collectors for applications in hot and humid climates. The use of ‘solar cogeneration’ by means of PV/t hybrid collectors enables the simultaneous production of electricity and heat, which can be directly used by desiccant air handling units, thereby making it possible to achieve very energy savings. The present work shows the results of detailed simulations conducted for a set of desiccant cooling systems operating without any heat storage. System performance was investigated through h…
Exergoeconomic analysis as support in decision-making for the design and operation of multiple chiller systems in air conditioning applications
2020
Abstract Multiple-chillers systems represent viable solutions for medium/large-scale air conditioning applications characterized by variable cooling demand. The energy efficiency of such systems is influenced by the number of chillers, the combination of cooling capacities, and the load-sharing among the units. Large efforts have been devoted to developing efficient operation strategies for these systems, but rules of thumb are usually adopted for selecting cooling capacities thus leaving room for energy and economic savings. In this paper, exergoeconomic analysis is proposed as a promising method to identify near-optimal design and operation strategies, due to the capability of exergoecono…
Life cycle performance assessment of small solar thermal cooling systems and conventional plants assisted with photovoltaics
2014
Starting from the results of a Life Cycle Assessment of small solar assisted heat driven chillers, the application of such methodology has been extended to systems with a conventional compression chiller assisted by a photovoltaic plant (PV). This study aims to provide a comprehensive compared investigation of these two families of solar assisted cooling systems (with solar thermal or PV). Results indicate that, in many cases, the systems with the PV grid connected plant performed best. In addition, two more configurations were investigated to further define the PV assisted systems, which minimise their interaction with the grid through the use of electricity storages. These systems performed…
Obraz Hrista v romane Čingiza Ajtmatova "Plaha"
2011
Aitmatov introduced a biblical motif into his novel – he chose Christ examination by Pilate. The writer extended the meaning of the scene, he altered its essence and “genre,” changing it into philosophical disputation. He also invented the story of Christ sailing with his mother on the Nile and their miraculous rescue by a crocodile. These scenes are presented in such a way that they remind the myth of the birth and death of Christ which allows rating Aitmatov's figure of Christ to the fifth category of literary embodiment of Christ proposed by T. Ziołkowski and called CHRIST AS A MYTH. A figure of Christ in the novel is a symbol of the highest perfection of humanity.